package com.dhj.jvmstudy.chapter06;

import jdk.internal.org.objectweb.asm.ClassWriter;
import jdk.internal.org.objectweb.asm.Opcodes;

/**
 * OutOfMemoryError: metaspace 元空间内存溢出
 * -XX:MetaspaceSize=10m -XX:MaxMetaspaceSize=10m
 */
public class OOMTest extends ClassLoader {

    public static void main(String[] args) {
        int j = 0;
        try{
            OOMTest test = new OOMTest();
            for(int i=0; i<10000; i++){
                // 创建ClassLoader对象，用于生成类的二进制字节码
                ClassWriter classWriter = new ClassWriter(0);
                // 指明版本号、修饰符、类名、包名、父类、接口
                classWriter.visit(Opcodes.V1_8, Opcodes.ACC_PUBLIC, "Class_"+i, null, "java/lang/Object", null);
                // 返回byte[]
                byte[] code  = classWriter.toByteArray();
                // 类的加载
                test.defineClass("Class_"+i, code, 0, code.length); // Class对象
                j++;
            }
        } catch (Exception e){
            e.printStackTrace();
        }finally {
            System.out.println(j);
        }
    }

}
